Peculiarities of formation of microbial cenosis of gray forest soil with different fertilizer systems in the agrocenosis of winter wheat

Abstract

Goal. To study the formation of the number, structure, and qualitative composition of the microbial biome of gray forest soil in the cultivation of winter wheat under different fertilizer systems. Methods. The number of microorganisms of the main physiological groups was determined by the method of microbiological sowing of soil suspension on nutrient media. The structure and qualitative composition of soil microbiota were studied by generally accepted methods for morphological and cultural properties. The diversity of soil microbial complexes was assessed by the Shannon and Simpson ecological indices. Results. The number of microorganisms of different physiological groups varied depending on the fertilizer system (from 0.9 to 27.5 million CFU/g of soil). Application of mineral fertilizers in the dose of N100P60K100 caused a decrease in the number of microorganisms of all physiological groups compared to other fertilizer systems by 1.1 – 3.5 times. With the application of organomineral bioactive fertilizers (OMBF), cattle manure, and the combined use of cattle manure with mineral fertilizers at a dose of NN100P60K100, the number of microorganisms increased by 3.5 times. It was found that the microbial soil biome was differentiated by the number of detected morphotypes (bacteria — 35 – 46, micromycetes — 16 – 20, actinomycetes — 20 – 25) and the structure of their distribution (0.62 – 16.36%). The greatest diversity of bacteria, micromycetes, and actinomycetes (according to the Shannon and Simpson indices) was found for the introduction of cattle manure, the least — for mineral fertilizers (bacteria and actinomycetes), and the introduction of OMBF (micromycetes). The bacterial microbiota was characterized by the greatest species richness. Conclusions. The use of different fertilizer systems in the winter wheat agrocoenosis significantly affects the formation of microbial coenosis in the arable layer of gray forest soil, which is manifested in the differentiation of quantitative composition, structure, and diversity of microorganisms and redistribution of functional activity of microbial soil.